Drugs destroy your ability to make good decisions. They are essentially hot wiring the brain's reward circuits which directly feed back into the brain's decision making processes. Most obviously, it's almost never the case that addicts consciously choose to become addicted.

"Drugs destroy your ability to make good decisions. They are essentially hot wiring the brain's reward circuits which directly feed back into the brain's decision making processes."

This reeks or propaganda based on a little bit of truth. Sure, being addicted to something warps your brain. It doesn't have to be drugs to do this, though. Gambling addiction is a menace for a subset of population too.

Sure, actually being on drugs will affect the way you think for a short time until it wears off. Some drugs might change your perspective on life (LSD and MDMA are common here).

But seriously: It also isn't as bad as you say.

Caffeine and nicotine aren't going to destroy your ability to make good decisions. Drinking moderately won't do that. You probably have worked with folks that were daily pot smokers your whole life without knowing. Some of them were alcoholics (admittedly, it'll warp some things, but a functional alcoholic tends to make good decisions to a point). A smaller number did heavier drugs occasionally: LSD a few times a year, cocaine 2-4 times a year.

And they've pretty much all retained the ability to make good decisions, even if they've made some you don't agree with.

Pretty sure that Erdos said that Dexedrine/variants of amphetamine made him want to do math.

Is wanting to do math a not good decision? Potentially, I guess.

If you are Erdos, it is a good decision.

Does anyone 100% consciously choose anything? If you make a decision after drinking a strong cup of coffee, how much of that decision came from the caffeine, and how much came from your “consciousness”?

I’m not necessarily disagreeing with you—addiction is a disease of forces and circumstances, for sure—but the level of “free will” present in any choice (or sequence of choices) is a certainly not amenable to a binary classification.

Yes, the degree "free will"/willpower factors into a decision is much more of a spectrum than a binary. I'm just pointing out that drug addiction shifts your decisions away from the free will end of the spectrum.

"Drug addiction" is not a singular problem with a singular solution. Every drug has unique effects, even between different people (two people take the same drug and don't have the same result). It does not serve public health to shoehorn everything into a square hole.

But the harm or benefit of a policy is not measured by how many specific decisions are performed, but rather by the overall effect of the policy on the community, no? So let's just talk about that rather than counting steps between A and B.

The overall harm or benefit to the community is certainly related to how many and likely those bad decisions are that result in a specific harm/benefit.

Something like this? https://www.vox.com/2014/5/19/5727712/drug-alcohol-deaths

Well yeah. I'm all for locking up drunk drivers, offering rehab and then permanently revoking their drivers licenses if they do it again. That goes to the second decision to adversely affect others.

If true, then you should be able to make that case directly, no?